The Advisory Council on Underwater Archaeology is pleased to present the 2009 ACUA Underwater Archaeology Proceedings from the Society for Historical Archaeology's 42nd Annual Conference on Historical and Underwater Archaeology, held in Toronto, Ontario. The underwater proceedings have been a hallmark of this annual conference for over 40 years. They provide a record of the development of underwater archaeology as a profession and include research from across North America and around the world. After an interruption in their publication, the ACUA Underwater Archaeology Proceedings returned in 2007. They continue to grow, and this year's edition presents underwater archaeological research extending from the Yukon to Panama, and from Hawaii to France. Each paper in this volume was presented at the conference in an organized symposium or session.
